JPH04117214A - Circular saw blade - Google Patents

Abstract

PURPOSE:To obtain a circular saw blade having shortened redressing time and improved cutting quality and work efficiency by providing the outer circumference of a flat circular saw body at regular intervals with plurality of teeth furnished with an outer edge having a prescribed clearance angle and forming a step having a specific length at the back of the outer edge part. CONSTITUTION:The objective circular saw blade 1 for bush cutter, etc., to cut weeds, bottom grass, shrub, etc., and driven by a motor, engine, etc., has the following structure. The outer circumference of a flat circular saw body 3 is provided, at regular intervals, with plurality of teeth 5 furnished with an outer edge part 15 having a prescribed clearance angle beta and a step 17 formed by contracting the rear part of the outer circumference 15 to a distance r2 which is shorter than the distance r1 from the grinding jig attaching hole 19 formed on the saw body 3 for grinding the teeth edge 11 of the teeth 5 to the outer edge part 15 by about several mm. The grinding width l of the outer edge part 15 can be shortened by this structure to enable the shortening of the redressing time and improve the work efficiency.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Field of Industrial Application) The present invention is a brush cutter, etc. that is rotationally driven by a drive source such as a motor or an engine, and is used for cutting weeds, undergrowth, shrubs, etc. This article relates to a new circular saw blade.

(Prior art) Generally, circular saw blades used for brush cutters etc. are, for example, SK
A plurality of teeth are provided at equal intervals on the outer periphery of a circular flat saw base material made of carbon tool steel of grade 5. Furthermore, each tooth is provided with an outer edge portion having a predetermined relief angle, and together with the rake angle provided on the inside, forms a tooth tip portion.

(Problem to be Solved by the Invention) By the way, the above-mentioned circular saw blade has a plurality of teeth provided on the outer periphery of the saw blade (saw base material) at equal intervals, and each tooth has a predetermined clearance angle. An outer edge was formed. Therefore, there is a problem in that the polishing width of the outer edge becomes large during repolishing, and it takes too much time for repolishing a plurality of teeth. Shortening this polishing time was an important issue.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an object of the present invention is to provide a circular saw blade in which the polishing width of the outer edge portion is shortened, the re-polishing time is shortened, and the work efficiency is improved.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a plurality of teeth each having an outer edge portion having a predetermined clearance angle on the outer periphery of a circular flat saw base material. are provided at equal intervals, and the outer edge is a distance shorter by several liters than the distance from the polishing jig mounting hole provided in the saw base material to the outer edge for polishing the tips of the teeth. This is a circular saw blade characterized by having a stepped portion which is provided by reducing the rear portion of the portion.

(Function) By employing the circular saw blade of the present invention, a plurality of teeth forming an outer edge having a predetermined clearance angle are provided at equal intervals on the outer periphery of the circular flat saw base material, and the teeth of the teeth are arranged at equal intervals. In order to polish the tip, the step part is formed by reducing the rear part of the outer edge part by a distance that is several inches shorter than the distance from the polishing jig attachment hole provided in the saw base material to the outer edge part. By providing this, the polishing width of the outer edge is shortened, the repolishing time is shortened,
In addition to improving work efficiency, the biting during cutting work is appropriately controlled, and it has a backup function for the tooth tip.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a schematic diagram of an embodiment of the circular saw blade of the present invention, and FIG. 2 is a plan view of FIG. 1. In the figure, circular saw blade 1
The saw base material 3 is made of carbon tool steel such as 5KS5 or 5KS6, and is made up of a plurality of teeth 5, 12 in this embodiment, arranged at equal intervals around the outer circumference of a saw base material 3 made of carbon tool steel such as 5KS5 or 5KS6. Each tooth 5 is formed with a tip portion mm consisting of a scooping surface 13 and an outer edge portion 15, and a stepped portion 17.

A circular saw blade mounting portion 9 consisting of a mounting hole 7 having a radius r from the center S0 is formed at the axial center of the saw base material 3. A drive shaft (not shown) that is rotatably driven by a drive source such as a motor or an engine is mounted in the mounting hole 7 . Therefore, in this installation, the drive shaft is mounted in the hole 7 of the part 9, and by rotating the drive shaft, the circular saw blade 1 is rotated in the counterclockwise direction of the arrow direction P.

A plurality of pieces are provided on each tooth side band in the saw base material 3 corresponding to the teeth 5,
In this embodiment, there are 12 polishing jig mounting holes 1, the same number as the teeth 5.
9 is provided. That is, each tooth 5 is placed on the circumference of the circular saw blade mounting portion 9 with a radius R0 from the center S0 of the mounting hole 7.
Mounting holes 19 for each jig are arranged corresponding to the respective jigs.

By providing each of the mounting holes 19 as described above, when a crack occurs from each tooth 5, this crack is received by the mounting hole 19, so that the tooth is not chipped and is prevented from scattering. There is. Therefore, safety in the cutting process is maintained.

In addition, when the tooth tip mm of each tooth 5 is worn, a polishing jig is attached to the mounting hole 19 corresponding to the worn tooth tip mm,
By swinging the circular saw blade 1, each tooth tip mm can be easily polished, and by this polishing, a predetermined relief angle β (for example, about 20 degrees) can be provided at the outer edge 15. I can do it.

The stepped portion 17 is larger than the distance (radius) “1” from the center St of the polishing jig mounting hole 19 to the outer edge 15.
Distance (radius) to 7: 2 is several mm, in this example 2+
The step 16 is formed by shortening the outer edge portion 15 by approximately +v~5 mm and reducing the rear length of the outer edge portion 15. The several square steps 16 between the outer edge portion 15 and the step portion 17 are located at the tooth tip m.
It gradually decreases with repeated polishing of m, but the outer edge 1
5 as a reference, the stepped portion 17 is formed by re-polishing to a specified step, and the function of the stepped portion 17 can be maintained.

In addition, the length l of the outer edge portion 15 from the tooth tip mm is appropriately selected depending on the size of the outer diameter of the circular saw blade 1 and the number of teeth, but in this embodiment, it is approximately 20ev, and the length l of the scooping surface 13 is The scooping angle α is selected to be about 40 degrees in this embodiment.

Therefore, by providing such a stepped portion 17, when re-polishing, the strength of the tooth tip mm is not impaired.
The polishing length of the outer edge portion 15 is shortened to 1, the polishing time is shortened, polishing efficiency is improved, and the weeds are appropriately controlled during cutting of weeds, etc., and the tooth tip mm is backed up. It has improved functionality, has better machinability and sharpness compared to conventional circular saw blades, and improves work efficiency.

Further, the tip portion mm of each tooth 5 is subjected to hardening heat treatment. As shown by the diagonal lines in the figure, the hardness of the tooth tip mm is determined by Rockwell C hardness (RC) by subjecting the tooth tip mm to high temperature heat treatment (quenching treatment) using, for example, laser or high frequency.
For example, it is made hard to about 58 to 60 mm to prevent wear of the tooth tips mm.

Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented in other embodiments by making appropriate design changes, and as already clear from the above description. The circular saw blade of the present invention includes a plurality of teeth provided at equal intervals on the outer periphery of a circular flat saw base material, each having an outer edge portion having a predetermined relief angle, and a polishing jig provided on the saw base material. The problems of the prior art can be effectively solved by reducing the rear part of the outer edge to provide a stepped part by a distance that is several inches shorter than the distance from the tool mounting hole to the outer edge. Compared to the circular saw blade of This has the effect of controlling weed infestation and improving the backup function of the tooth tips.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a circular saw blade of the present invention, and FIG. 2 is a plan view of FIG. 1. 1... Circular saw blade 5... Teeth 9... Circular saw blade mounting part 15... Outer edge 19... Polishing jig mounting hole 3... Saw base material 7... Mounting hole mm. ...Tooth tip part 17...Step part agent

Claims (1)

[Claims] A plurality of teeth each having an outer edge portion having a predetermined clearance angle are provided on the outer periphery of a circular flat saw base material, and are provided at equal intervals, and a polishing device provided on the saw base material to polish the tips of the teeth. A circular saw blade comprising a stepped portion that is provided by reducing the rear portion of the outer edge portion by a distance that is several mm shorter than the distance from the jig attachment hole to the outer edge portion.